Why does helium change your voice?

We have all tried at some time to try inhaling helium or at least watching videos of it. Why does it make us all sound squeaky and high pitched? Actually. helium does not change the pitch or frequency of your voice. What it does is, it fills your voice box as a gas that is much lighter than air. This makes the vibrations of sound waves travel a lot faster than in air and it increases the wavelength, making the change in resonance that we hear as a higher pitch. When your vocal chords vibrate, they do so at many different frequencies. This mix is what defines the quality of sound. The helium makes the higher pitched tomes resonate more while doing the opposite to the lower tones. You can also enhance your lower tones similarly by inhaling sulfur hexafluoride.